Spectroscopy

Question 1

What is spectroscopy?

Answer 1

The use of the absorption, emission or scattering of electromagnetic radiation by matter to study the matter or to study the physical processes. The matter can be atoms, molecules, atomic or molecular ions, or solids

Question 2

What happens with an infrared spectrometer?

Answer 2

A beam of infrared radiation is passed through a sample. , spectrometer then analyses the amount of radiation transmitted through the sample as the incident radiation is varied. Ultimately a graph results, showing the transmittance of absorption versus the frequency or wavelength of the incident radiation

Question 3

What are intramolecular rotations?

Answer 3

The rotations of a molecule about its centre of gravity.

Rotational energy is quantised and gives rise to absorption spectra in the microwave region of the electromagnetic spectrum

Question 4

What are intramolecular vibrations?

Answer 4

The bending and stretching motions of bonds within a molecule.

Relative spacing between vibrational energy levels increases with the increasing strength of an intramolecular bond. Vibrational energy is quantised and gives rise to absorption spectra in the infrared region of the electromagnetic spectrum

Question 5

Why is IR spectroscopy useful?

Answer 5

By looking at the characteristic transmittances of a compound’s spectrum, it is possible to identify the functional groups present in the molecule

Question 6

What is Nuclear Magnetic Resonance (NMR) spectroscopy used for?

Answer 6

Can be used to examine the environments of the hydrogen atoms in a molecule. One can determine both the numbers and types of hydrogens in a molecule. Relates to the magnetic properties of the hydrogen protons, spin